Control device for fluid power transmitters



Oct. 6, 1942. F. CANAAN 2,298,105

- CONTROL DEVICE FOR FLUID POWER TRANSMITTERS Filed Jan. 16, 1940 2 Sheets- -Shet 1 FAIC CAN/IAN,

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3W ism Oct. 6, 1942; F. CANAAN 2,298,165

CONTROL DEVICE FOR FLUID POWER TRANSMITTERS Filed Jan. 16', 1940 v -2 Sheets-Sheet 2 Jmmm l-Tmc CANAAN.

Patented Oct. 6, 1942 zasaros coNrlior. nsvrcs Fon FLUID rowan rnansrn'r'rsas Falc Canaan, Heidenheim-on-the-Brena,

Application January 16, 1940, Serial No. 314,037

6 Claims.

This invention relates to .hydraulic power transmitters and in particular to controldevices for emptying the working circuits of such transmitters.

One object of this invention is to provide a 'fluid power transmitter wherein the filling and emptying of the working chamber is controllable at will by the operator, the emptying being carried out at a rapid speed.

Another object is to provide a fluid power transmitter, such as a hydraulic coupling, wherein peripheral discharge ports are closed by thin plates carried by'an expansi-ble bellows.

Another object is to provide a fluid power transmitter as set forth in the preceding object, wherein the interior of the bellows is in communication with the filling conduit for the transmitter. I

Another ob ect is to provide a fluid power transmitter having peripheral emptying ports closed by thin plates mounted on expansible bellows, the interior of each bellows being in communication with the exterior of the transmitter, such as the atmosphere.

Another object is to provide a fluid power transmitter having peripheral emptying ports closed by thin plates mounted on elastic or expansible bellows, one side of the plates being in communication with the filling conduit for the working chamber and also connected with the exterior of the coupling by a port which is smaller in cross section than the cross section of the fluid supply conduit leading to the chamber in which the plates and bellows are mounted.

This application is a continuation in part of my copending application, Serial No. 107,741, filed October 26, 1936, now Patent No. 2,186,956.

In the drawings: 1

Figure 1 is a longitudinal section through a part of a fluid power-transmitter equipped with the peripheral emptying ports andbellows-operated plate valve members of this invention.

Figure 2 is an enlarged-view of the upper portion of Figure 1 containing the bellows-operated valve. Figure 3 is a view similar to Figure 2 but showing a modification wherein the interior of the bellows stands in communication with the exterior of the transmitter, such as with the atmosphere.

In general, the fluid power transmitter of this invention consists of a casing having a plurality of rotors and containing a plurality of peripheral emptying ports. These emptying ports are closed by small discs or plates mounted on an expansi- Germany November 1, 1935 ble member consisting of an elastic bellows. By expanding and contracting this bellows the emptying ports can be opened or closed at the will of the operator. In one form of the invention the interior of the bellows is connected to the filling conduit for the working chamber so as to be expanded when the chamber is filled,

thereby closing the emptying ports. In a modification of the invention (Figure 3) the interior of the bellows stands in communication with the exterior of the transmitter, such as with the atmosphere.

Hitherto with previously known fluid power transmitters, such as hydraulic couplings, the emptying of the working chamber has been effected by peripheral ports which are constantly open so that the leakage loss occurring during running is counteracted by means of a filling pump. To empty the working chamber, the filling pump is merely halted whereupon the fluid in the working chamber escapes by centrifugal force through the peripheral ports. In other types of hydraulic power transmitters, relatively heavy valves, guided in suitable guides, have been used for controlling the emptying ports. The centrifugal force arising from the weight of these valves has required additional pressure to keep them shut, and these valves have been subject to seizure when their surfaces have been fouled by dirt or other foreign matter in the 7 working fluid.

nated. The valve plates or discs are preferably of thin iron or other metal, leather, India rubber;

or otherflexible material and do notrequire the high-pressure of fluid necessa'ry'in previous arrangements for keeping the valves closed while contraction of which the emptying ports are the fluid power transmitter is full and running. Moreover, in the present invention the discs or plates are mounted upon expansible members such as elastic bellows, by the expansion and and 2 show a fluid power transmitter, such as a hydraulic coupling,having shafts H and I2 carrying rotors I3 and I4 equipped withblades or vanes I5 and i6 bounded by core rings l1 and I8 respectively. Between the rotors l3 and I4 is located the working chamber I8 of the transmitter. The outer wall 20 of the rotor l4 and its extension 2| form a casing or housing enclosing the rotors and surrounding the working chamber l3.

In order to provide for emptying the working chamber IQ of the working fluid, the casing 20 is provided with radial bores 22 having transverse ports 23 leading therefrom to the exterior of the coupling. The bores 22 are provided with threaded counterbores 23a. for receiving the correspondingly threaded portions of tubular valve casings 24 containing internal chambers 25 com'-. municating by the ports 26 with the ports 23. The casings 24 also contain the emptying ports 21 interconnecting the working chamber IS with the valve casing chamber 25.

Mounted in the valve casing chamber 25 (Fig ure 2) is an expansible bellows 28 having a plateiike end 29 carrying the disc-shaped valve member 30. r

The bellows 28 is secured at its upper or open end to the casing 24 and opens into the outer chamber 3|. Leading from the outer chamber 3| is a leakage port 32 of relatively smaller diameter of cross section than the entrance port or inlet port 33 by which pressure fluid is ad- 4 mitted to the interior of the bellows 28. The motion of the end 29 of the bellows 28 is limited by the cap screw 34 threaded through the bore 35 in the valve casing 24.

The inlet port 33 communicates with an inlet passageway 36 leading through the casing portion 2| to a chamber 31 surrounding the shaft H. The chamber 31 is in communication with the filling member 38 having the filling passageway 39 connected to the filling conduit 48. The latter is connected to a filling pump (not shown) and is provided with a valve 4| which may be opened or closed to control the filling of the fluid power transmitter. The working chamber H! of the latter is filled from the chamber 31 by a shaft passageway 42 leading therefrom through the shaft to its end.

In the operation of the fluid power transmitter shown in Figures 1 and 2, the filling pump is started in operation and the valve 4| opened so that liquid flows through the conduit 40, passageway 39, chamber 31 and shaft bore 42 into the working chamber l8, filling the latter to the desired point. At the same time, pressure fluid flows through the passageway 36 into the interior of the expansible bellows 28 and expands each bellows, causing its valve member 30 to tightly engage and close its adjacent port 21. 'A small escapes through the port 21, the port 25 and the port 23 to the exterior of the transmitter. Any particles of dirt in the working fluid will ordinarily be swept away by the fluid itself and cannot interfere with the seating of the valve members 30 against the ports 21. A slight temporary leak due' to a dirt particle does not adversely affect the normal operation of the hydraulic power transmitter, since the small leakage losses are made good by the filling pump. The emptying ports 21 in the valve casings 24 mounted in the bores 22 are ordinarily formed in the driving part of the fluid power transmitter. so that centrifugal force is always present for the emptying of the working chamber ll. Under these conditions, the shaft 2 and rotor 4 are the driving elements and the shaft II and rotor I3 the driven elements.

While the coupling or hydraulic power transmitter is being emptied through the emptying ports 21, the fluid within the bellows 28 and passageways 36 escapes through the leakage ports 32 to the exterior of the casing so that this part of the apparatus is also quickly emptied. The

volumes of these control chambers and passages. 3| and 36, are kept as small as possible so that their total volume amounts to not. more than five percent of that of the remainder ofthe circuit. In this manner, the rapidemptying of the circuit is made possible since the greater part of the liquid present in the interior of each bellows and the communicating chamber 3| and passage 36 must escape through the small port- 32 before the valve members 30 can open to their fullest extent, as governed by the cap screws 34.

It will be understood that the leakage ports 32 are of smaller cross sections than the inlet ports or passageways 36, so that when the filling pump is operating and the coupling is being filled, pressure fluid will be supplied more rapidly to the interior of each bellows 28 than it can escape through the leakage port 32.

In the modification shown in Figure 3 the port 21 in each valve casing 24 is provided with an outwardly extending tubular portion 56 terminating in a valve seat 5|. The latter is engaged by a thin disc-like valve member 52 attached to the bellows 53 at the outer end thereof. The inner end of each bellows 53 is secured to a flange '54 forming a part of the valve casing 24 and eration of the filling pump fills the outer chamber 3| of the valve casing 24 with pressure fluid, at the same time filling the working chamber l3. Since the interior of the bellows 53 is in communication with the atmosphere, it is quickly collapsed and the disc-like valve member 52 forced inwardly against the valve seat 5|, closin the emptying ports 21. These ports'-21 remain closed evenv under the action of centrifugal force upon the liquid within the working chamber l9 because of the greater area of the valve discs 52 on their outer sides than on their inner sides. When it is desired to empty the working chamber IS, the valve 4| is closed or the filling pump halted as before. Pressure fiuid then escapes from the valve operating chambers 3| through the leakage ports 32 and centrifugal force acting upon the liquid within the working chamber l3- forces the liquid outward against the valve plates or discs 52, forcing them away from their seats BI and permitting the liquid to escape through the interior of the bellows 53 and passageways 51 outward through the annular chambers 56, ports 58 and ports 23.

It will be understood that I desire to comprehend within my invention such modifications as come within the scope of the claims.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a hydraulic power transmitter, a working chamber, a driving rotor and a driven rotor therein, an emptying port leading out of said working chamber, a thin valve plate or lamina ciosingly engageable with said emptying port, a control chamber, a bellows communicating with said control chamber and supporting said valve said control chamber, said bellows being expansible to press said lamina against said emptying port in response to the admission of pressure fluid plate or lamina, and means for supplying pressure fluid to said control chamber to move said thin flexible plate closingly engageable with said emptying port, a control chamber, a bellows communicating with said control chamber and connected to said valve member, and means for supplying pressure fluid to said control chamber to move said bellows for closingly engaging said valve member with said emptying port, the area 01' the valve member surface acted upon by the pressure fluid within said control chamber being greater than the valve member surface acted upon by the pressure fluid at said emptying port.

3. In a hydraulic power transmitter, a working chamber, a driving rotor and a driven rotor therein, an emptying port leading out'of said working chamber, a sealing lamina closingly engageable with said emptying port, a control chamber, a bellows communicating with said control chamber and supporting said sealing lamina,

and means for supplying pressure fluid to said having its exterior communicating with said control chamber, a valve member in form of a relatively thin plate mounted on said bellows and closingly engageable with said emptying port, and means for supplying pressure fluid to said control chamber to contract said bellows and press said valve member against said emptying port.

5. In a hydraulic power transmitter, a working chamber, a. driving rotor and a driven rotor therein, an emptying passageway leading out of said working chamber, a control chamber, a bellows having its exterior communicating with said control chamber and having its interior in continuous hydraulic communication with an exhaust, a lamina mounted on said bellows and separating said control chamber from said passageway, said lamina being movable selectively into a first position to directly connect said pas- -sageway with said exhaust through said beliows, or 'into a second position for interrupting hydraulic communication between said passageway and the interior of said bellows, and means for supplying pressure fluid to said control chamber to move said lamina into said second position.

6. ma hydraulic power transmitter, a working chamber, a driving rotor and a driven rotor therein, an emptying port leading out 01' said working chamber, a control chamber, a bellows supported by said driving rotor and having its exterior communicating with said control chamber, a valve member mounted on said bellows and closingly engageable with said emptying port, and means for supplying pressure fluid'to said control chamber to contract said bellows and close said valve member against said emptying port, said valve member comprising a relatively thin flexible plate mounted upon said bellows.

FAIC CANAAN. 

